1. Field of the Invention
The present invention is in the field of hydraulic accumulator devices and pertains more particularly to a hydraulic accumulator which is inexpensive to fabricate, and to the method of making the same.
2. The Prior Art
The use of accumulator devices in various hydraulic applications is progressively increasing. Heretofore the relatively costly nature of accumulators has discouraged their use in certain environments and applications where cost is a significant factor.
Typically, an accumulator comprises a pressure vessel or shell divided into two chambers by a resilient bladder member, one said chamber being connected to a gas charging port having a valve and the other said chamber being connected to an oil port which is, in turn, adapted to be connected to a hydraulic line.
Mounting of the bladder within the vessel has usually been accomplished by providing a retainer ring or the like to which the open mouth portion of the bladder is connected either by bonding or molding thereover. The retainer is thereafter secured at a desired position within the shell as by welding.
Thereafter a cover member is affixed to the open mouth portion of the device.
The operation of separately forming the bladder and retaining ring assembly and securing the retaining ring in position has added materially to the cost of fabrication. This is especially true where the ring is weldingly connected to the pressure vessel since great care must be taken in the course of formation of the weld to avoid communicating undue heat to the bladder.